The use of LED's for light-emitting displays on a variety of objects is well known.
Rectangular matrices of LED's with appropriate control circuitry, to display scrolling messages of any length, including symbols, graphics, and animated images, are often seen in public places (one famous example is in Times Square in New York City) displaying advertising or news messages by scrolling them across the width of the display. These are not suitable for use as jewelry, ornaments, or items of apparel, because they are too large and heavy, would not operate for long enough on a small enough battery, or are too expensive to manufacture.
It has long been recognized in the art that a longer display is advantageous in promoting readability. For example, U.S. Pat. No. 4,398,819, which is hereby incorporated by reference, discusses near the end of column 1 the difficulty in understanding a lengthy message when displayed in a “continuously rotating” format on a display, in that case on a photocopier control panel.
U.S. Pat. No. 5,767,822 discloses a way to reduce the number of LED's in a scrolling display, but this reference fails to suggest reducing the width or height of the display, as measured in pixels.
In some instances, such as U.S. Pat. Nos. 5,375,044, 5,575,554, 4,777,408, 4,254,451, which are hereby incorporated by reference, inventors have disclosed light-emitting displays on wearable items. Some provide a choice between a few different sequences of flashing pulses, but none allow a user to create a personal message, graphic, or animated image.
U.S. Pat. No. 4,303,996 discloses an LED watch that is capable of displaying up to five alphanumeric words of five characters each. The words are displayed sequentially using a linear array of five nine-segment displays, and there is no teaching of scrolling the words. The watch cannot display messages of more than five words or words of more than five characters. It cannot display graphics or animations. The display is not suited for use as a brooch, badge, or tiepin, as is the instant invention, so that people other than the wearer can read the message.
Personal digital assistants or organizers have been available for some time. One example, the Rolodex REX from Franklin is a credit-card-sized device weighing approximately 39 grams and fitting within a rectangular solid of volume approximately 29 milliliters and retailing for approximately US$99. It is powered from two CR2025 lithium coin cells, said to last up to six months in normal use. It uses an LCD display. It has five buttons and a PCMCIA connector. It does not have any means of attachment to a wearer. Its display is 160 pixels wide by 98 high, making it much more expensive than the present invention.
Absent from the prior art, however, is any indication of the use of a shorter display for scrolled characters or animations that has satisfactory readability yet low cost and weight, making it suitable for wearing.
The prior art does not recognize the tradeoff between readability and economy of a scrolling display.
Accordingly, a first object of the invention is to reduce, rather than to increase, the number of pixels, and therefore characters of text, in the width of a display, to minimize the size, weight, frequency of battery changes or battery size, and cost of manufacture, while still being able to display a full set of Arabic digits, Roman letters, and many other symbols, graphics, and animations.
Another object of the invention is to achieve a legible display while retaining the economy of few pixels.
Another object of the invention is to provide an ornament that (1) can display scrolling messages with a length limited only by the available memory in the control circuit (64 characters in a preferred embodiment), (2) that is wearable as a badge, brooch, or tiepin, or that can be included in a greeting card or novelty gift or used as a Christmas ornament or other ornament, and (3) that can display symbols, graphics, and animated images.
Another object of the invention is to provide a control system that retains flexibility yet has low cost and ease of programming.
Another object of the invention is to increase the display-control and message-editing functions available from just two buttons, allowing great functionality with reasonable convenience while keeping the number of buttons and hence cost and size to a minimum.
Another object of the invention is to provide a low-cost device that omits components commonly required in display devices, such as resistors and even an on-off switch.
Further objects and advantages of our invention will become apparent from a consideration of the drawings and ensuing description.